Apparatus for the reduction of argentiferous ores



0. LUMAGHI. APPARATUS 'POR THB vREDUCTION'OF ARGBNTIFBROUS GRES.

as l L *""J (No Model.)

l l l A. .f P

l., A /z UNITED STATES PATENT OEEICE.

OCTAVIUS LUMAGHI, OF ST. LOUIS, MISSOURI.

APPARATUS FOR THE REDUCTIONl OF ARGENTIFEROUS ORES.

SPECIFICATION forming part of Letters Patent No. 425,813, dated April 15, 1890. Application filed September Z2, 1888. Serial No. 286,067. (No model.)

To all whom it may concern:

Be it known that I, Oc'rAvrUs LUMAGHI, of St. Louis, Missouri, have made a new and useful Improvement in Apparatus for the Reduction of Argentiferous and other Zinc Ores, of which the following is a full, clear, and exact description.

This invention has for its obj ect, mainly, an

improved means for obtaining the spelter separate from the lead, silver, and gold, for btaining oxide of zinc, and for saving a large percentage of the silver and gold, which, when ores such as are under consideration are treated in contact with the atmosphere, are liable to be carried off with the oxide of zinc and other volatile metals.

My improvement is in part based upon the familiar construction known as the Belgian zincfurnace,7 in that the retorts employed yare arranged and heated as in that type of furnace, and it 'may also 'be considered an improvement upon or as related to the zincsmelting furnace patented to me October 23, 1877,No. 196,369, in that the upper end of the retorts is adapted to be opened to provide for an air-draft.

The essential elements of the improved construction are, first, the furnace-walls, fireplace, and iiues, which are constructed so that the retorts can be held and have the. heat applied to them in manner substantially as in the Belgian zinc-furnace; second, in the place of applying the condenser to the lower or charging end of the retort the application of it to the upper end of the retort; third, a retort substantially similar to the Belgian-furnace retort and adapted to be charged at its lower end, but also perforated at its upper end to provide for the escape at that end of the gases generated from the contents of the retort; fourth, the manner of combining the retort and the condenser sc that the zinc-vapors shall be readily condensed therein, and when condensed the spelter shall not flow back to the retort again; fifth, the means for closing the charging end of the retort; sixth, the mode 'of constructing that one of the furnace-walls where the condensers are applied to the retorts; seventh, the means for promoting the formation of oxide of zinc and its collection.

YTo fully-carry out the improvement, all the to the condensers.

elements above enumerated are needed in conjunction; but certain portions of the work can be accomplished with but a portion of the elements, as will appear in the following detailed description of the improved apparatus and its operation, aided by the annexed drawings, making part of this specification, in

which- Figure l is a vertical cross-section ofthe improved apparatus or plant; and Figs. 2, 3, and 4, details upon an enlarged scale, Fig.'2 being a view in perspective of one of the retorts with a condenser attached thereto, the View being toward the condenser and the upper end of the retort and looking upward; Fig. 3, a view in perspective, looking sidewise thereat, of the condenser and the upper portion of the retort; and Fig. 4, a vertical longitudinal section of the retort and condenser, the stopper used to close the lower or chargn ing end of the retort being shown detached and in side elevation.

The same letters of reference denote the same parts.

v A A Fig. l, represent the furnaces of the preferred con struction and arrangement. Two

of the furnaces are shown in combination. They are -arranged opposite each other and spaced sufficiently apart to provide a suitable space R for the operatives when attending The space R, by means of a roof O overhead, end walls D D, and doors d d at each end thereof, can be inclosed to form a chamber sufficiently tight to receive the gases4 escaping from theretorts through the condensers and enable them by means of an exhaust-flue-such as at E-to be Withdrawn from the space R and collected in some suitable receptacle (not shown) for receiving and collecting oxide of zinc. The furnacesA A can be used singly. In such case the space R can be made to connect with the single furnace used.

The furnace, so far as the general shape is concerned, resembles, as stated, the Belgian furnace.

a represents the fire-place of the furnace; c', the front wall; a2, the back wall; a3', the roof; d4, an end wall; c5, the support for thc lower end of the retort, and d6 the support for the upper end of the retort, all of which elements IOO .are substantially as in a Belgian'furnace, saving that the back wall a2 is perforated to admit the condensers, which project through the wall a2, as shown.

B Brepresent the retorts. So far as their size, general form, and composition are concerned they resemble those used in the con structions above referred to. They are adapted to be charged through the opening bin the lower end thereof, and then to be closed by means of the stopper b. The stop-` per is in the form of -a disk, notched at points b2 b2 b2, equidistant from each other, and when the stopper is placed in the retort one of the notches comes at the bottom and the othery notches somewhat above the center of the retort. The upper end b5 of the retort is closed, saving a central perforation b4, which is about two inches in diameter.

C represents the condenser, which is of the usual form, and is connected to the retort, inclined forward, and adj usted in accordance to the inclination of the retort in the furnace, so that a considerable portion of its interior C is below the level of the perforation'bl. Thus owing to the position of the retort and the condenser, both the retort and the condenser, inclinin g downward from their point of union, the distilled zinc gathered in the condenser cannot flow back into the retort, and any liquid lead or other metal that may have become liquefied during distillation, cannot reach thev distilled zinc in the condenser, but will iind its way to the lower end of the retort, where it may be recovered by tapping Vthe lowest notch of the retort-stopper b. An additional feature of this part of the construction is that, y the perforation b4 heilig only about one-third the inside diameter of the retort, the gases` generated therein are reduced in volumethat is, concentrated-in passing through the lreduced diameter, the velocity of the current. of gases being also proportionally increased,` thus reaching the condenser in the shape of` a jet of concentrated zinc-vapor, which, com, ing through the perforation b4 in a straight; line, strikes a limited area of the inclined condenser at its upper inner sidewith impact.E proportioned to the increased velocity of the,VK current of zinc-vapor, as shown by dottedl line, Fig. 4. 4 j

The cooler temperature of the inside of the condenser as compared to the same inthe re r tort, together with the increased impact cone, sequent to the increased velocity of the cur rent of zinc-vapor as it strikes the coolerh surface of the condenser, causes the complete condensation of the zinc-vapor into liquid;` metal and avoids the formation of zinc pow` der, which is the result of a too slow supply( of zinc-vapor. A

Another feature of this invention is in the construction of the dam C', made out of maf terial from the charge mixed with blue pow-1 der, which is placed inside the small opening j of the condenser-such as is `in common use inl this art-to regulate the flame and hold the spelter temporarily, that, thecondenser being properly adjusted and inclined, the highest point of the dam besomewhat lower than the lower margin of the perforation b4, so that the distilled zinc cannot iow back into the retort when suiferedto remain in the condenser until it overliows.

Another feature is forming a circular groove `b5 in the upper end of the retort, which in diameter disagrees with that of the end c4 of the condenser, the aim `being to provide a ready means for insuringthe proper relation of the condenser and "retort, for lhowever the retort or the condenser may' be turned around the condenser end c4 canenter the groove b5 but at one point-onlyand atother points be excluded therefrom, and asthat point is `naturally the lowest `point thercon'denser, however hastily it is-adjusted, will always as sume the proper inclination'for effecting the above-enumerated results.

The operation is asfollows: The retorts are placed inpositionin the furnace, as shown in Fig. l, and duly charged with the ores or other material and closed with the Stoppers and luted, and the furnace is fired, all in the customary manner. The condensersare applied as described and Vthe joint between the condenser and retort fluted. The spaces in the front and back walls of `the furnace around the retorts are also suitablyluted. That porj tion being hastenedby reason of the gaseousy current being caused to` encounter the upper inner sideof the condenserfasindicated by the arrow in Fig. 4,. Theusualsmall opening c5 is left above the dam in the outer end of the condenser for the usual flame to be burnt at that point. Owing to theiposition'of the condenser and its relation `to'the perforation b4, the liquefied speltercannot flow backinto the retort `and such lead and silver as may liquefy in the retort cannot enter the condenser. The spelter` can be Vwithdrawnfroln "the condenser in any suitable `manner and the liquid lead and silver, if any there be, can "be tapped `from the retort by opening the lowest notch inthe stopper. Thecontents of the retort can be reached with a poker, as when it is desired to scrape the shell of the retort to separatetherefrom `anything which `may collect upon it, by introducing the poker fthrough a 'perforation b2. "has been obtained andthe stage-ofthe oper- 'ation at whichthe remaining zinc is to berelcovered in the form of an oxide,'one of 'the upper notchesb2 in Vthestopper'b `is opened tto admit theouter air, which thenpasses into When the spelter IOO 1rof

land throughthe retortand thenthrou'gh the fcondenser, in :itsroute` coming in contactwith *the oresand formingoxide of'zinc. The gaseous current passesout into the space R, whence 5it is Withdrawn into the nue.

Any suitable means-such as an exhaustfan (not shown may be used to promote the movement of the air into theretorts and the discharge and delivery of the oxide of zinc into the flue. While this is going on, the doors to the space R should be closed. Such silver or gold as passes off with the zincoxide current is carried along with it and is ultimately collected with the oxide. Thus With the saine means, and, if desired, Without changing any part thereof, all the abovedescribed operations are carried on. The spelter is separately collected. The lead and such silveras liqueiies are collected by themselves. The zinc oxide is formed and 0btained, and the volatilized precious metal is saved. It may be added that the ore material remaining within the retort has in effect (and by reason of the heating to which'it has been subjected) been roasted, and thus made ready for subsequent treatment elsewhere and according to any of the well-known methods for the recovery of gold and silver. The roof to the space inclosed at the back of the furnace may have the shape indicated by the broken line 4, Fig. 1.

Any suitable means-such as fragments of bricks or retorts carefully lutedmay be used to close the lower end of the retort, provided the described perforation b4 is formed.

The opening h6 in the stopper b is merely vto receive a handle in manipulating the stopper. It is luted when the stopper is in place.

The opening b in the retort-stopper should be slightly above the center of the disk, so that on being manipulated with a handle one of the notches comes necessarily to the bottom.

Having thus fully described my invention, I claim as new and I desire to secure by Letters Patentl. The combination, with a furnace having openings at the front and back walls of the inclosure, connected to a suction device and having a tight roof and doors, of the retorts having their butt-ends perforated and the condenser applied thereto, as described, and for the purposes specified.

2. The combination of the retort, the condenser, and the retort-stopper, said retort at its upper end being perforated centrally and having an annular groove surrounding said perforation, and said condenser at its upper end being of a different diameter from that of said groove, and being applied vto the upper h end of said retort and to said groove, substantially as described.

3. The combination of the retort and the retort-stopper, said stopper being inserted and luted in the lower end of the retort and being in the shape of a disk notched at the periphery and having an opening slightly above the center, so that when the stopper is placed in the retort one of the notches comes at or near the bottom, substantially as described, and for the purposes specified.

Witness my hand.

` OCTAVIUS LUMAGHI. Witnesses:

C. D. MooDY, B. F. REX. 

